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L. O. HOWARD. Entomologist and Chief of Bureau. 




In Charge of Truck Crop and Stored Product Insect Investigations. 

Issued October 31, 1913. 






L. O. HOWARD, Entomologist and Chief of Bureau. 




In Charge of Truck Crop and Stored Product Insect Investigations. 

Issued October 31, 1913. 





L. O. Howard, Entomologist and Chief of Bureau. 

C. L. Marlatt, Entomologist and Acting Chief in Absence of Chief 

R. S. Clifton, Executive Assistant. 

W. F. Tastet, Chief Clerk, 

F. H. Chittenden, in charge of truck crop and stored product insect investigations. 

A. D. Hopkins, in charge of forest insect investigations. 

W. D. Hunter, in charge of southern field crop insect investigations. 

F, M. Webster, in charge of cereal and forage insect investigations. 

A. L. Quaintance, in charge of deciduous fruit insect investigations. 

E. F. Phillips, in charge of bee culture. 

A. F. Burgess, in charge of gipsy moth and brown-tail moth investigations. 

Rolla P. Cueeie, in charge of editorial work. 

Mabel Colcord, in charge of Horary. 

Truck Crop and Stored Product Insect Investigations. 

F. H. Chittenden, in charge. 

C. H. Popenoe, Wm. B. Parker, H. M. Russell, H. O. Marsh, M. M. High, 
John E. Graf, Fred A. Johnston. C. F. Stahl, D. E. Fink, A. B. Duckett, 
F. B. Milliken, entomological assistants. 

I. J. Condit, R. S. Yaile, collaborators in California. 

W. N. Ord, collaborator in Oregon. 

Thos. H. Jones, collaborator in Porto Rico. 

Marion T. Van Horn, Pauline M. Johnson, Anita M. Ballinger, Cecilia 
Sisco, preparators. 



Introduction 5 

The moth 5 

The egg 6 

The larva 6 

The pupa and cocoon 6 

Historical 7 

Life history 8 

Remedies 9 


Fig. 1. The rose slug-caterpillar (Euclea indetermina) : Stages 7 


8885°— 13 


(Euclea indetermina Boisd.) 


It is only within comparatively recent years that the slug-like 
caterpillar, Euclea indetermina Boisd., has been known to injure the 
rose. In August, 1905, the Bureau of Entomology received two 
reports of attack to the foliage of rosebushes by this species. The 
insect has, however, been previously observed to have this food habit. 

August 15, 1905, Dr. A. D. Hopkins furnished specimens of the 
larva from Kanawha Station, T\ r . Va., stating that a dozen or more 
individuals could be found feeding on the leaves of a single rosebush. 
By August 20 the specimens received had transformed to pupse. 
During the last week of August the same species, accompanied by 
specimens of both the penultimate and last stages, was received from 
Mr. S. D. Nixon, with report that it was injuring roses at Balti- 
more, Md. 

The rose slug-caterpillar has been figured and described in its 
various stages, but is not a common species and, therefore, not well 
known. It is, however, strongly and attractively marked and very 
interesting in its transformations, resembling in some particulars the 
more common and related saddle-back caterpillar ( [Empretia] Sibine 
stiniidea Clem.). The accompanying illustration (fig. 1), notes, and 
brief descriptions have been brought together as of interest to rose 
growers and also to nurserymen, for the caterpillars also attack 
young trees and shrubs. It is in the last two stages of its larval 
existence that this species attracts most attention. The moth which 
it produces is less often seen. 


In its adult stage this insect is nearly as attractive as the larva. 
Its coloration is unusual in the boreal American fauna. The general 
color is pale cinnamon brown ; the forewings are darker and crossed 
diagonally by a green band, which occupies more than half the 
wing, leaving a wide border of darker brown and an inner or basal 
area of the same color and of the form shown in figure 1, a. The 
hind wings and the underside of the wings are nearly uniform pale 
brown, as is also the body, except on the edges of the wings and 
the tip of the abdomen. The thorax is like green plush. The wing 



expanse of the male is generally a little less than an inch; of the 
female, a little more. 

The moth closely resembles (Parasa) Euclea chloris H.-S., for 
which it has often been mistaken. 1 



The egg is described by Dr. H. G. Dyar as follows : 

Singly, or in small groups, slightly imbricated. Elliptical, flattened, translu- ^ 
cent pale ochre-yellow on glass, 1.5 by 9 mm. ; reticulations obscure, possibly 
only in a strong light, rounded hexagonally, nearly linear, somewhat irregular. 
No special characters. They hatch in nine days. \ 



-...;■. i 

The following is descriptive of the larval forms received from 

"West Virginia and Maryland, but according to other describers the ? 
general color varies from red to sulphur-yellow. 

The penultimate stage. — In the penultimate stage the larva closely 
resembles the mature form, but the prominent spine-bearing processes 
are paler and less reddish, being chiefly of a dull lemon-yellow color, ( 
with the exception of the small lateral spiny tufts, which are orange 
at the base. Between the third and fourth processes the dorso-lateral 
stripes are distinctly carmine. The length of the slug-caterpillar at 
this stage is about half an inch or a little more. 

The full-grown larva. — The full-grown larva looks very unlike 
any common species with which it could be compared, but in the 
general arrangement of its spines it resembles Sibine stimulea. Its 
form is similar, but the general impression as to color is orange, 
which is the color of the principal spine-bearing processes, of which 
there are seven pairs, as follows: Two in front, two behind, one 
pair in the middle, a shorter pair proceeding from the first thoracic -• 
segment just above the head, and the seventh pair proceeding from the , 
second thoracic segment on each side. There is a dorso-lateral 
vermilion-scarlet stripe bearing six pairs of moderately long spinous ' 
processes and four rosette-like spinous tufts. There is also a lateral z 
red stripe and a sublateral red stripe bearing nine rosette-like spi- 
nous tufts. The thin violet or mauve lines, in the middle of the back, 
as shown in figure 1, c, alternate with white. The length is about h 
three-fourths of an inch. 



The pupa (fig. 1. /) is so similar to that of Sibine stimulea that a 
detailed description is not necessary for present purposes. It is a / 
trifle smaller than the latter, and in its early stage pale yellow with A 

1 Both species belong to the family Cochlidiidae. \ 


pale brown eyes and palpi. It measures about three-eighths of an 
inch in length. The hornlike process extending above and between 
the eyes is prominent. 

The pupal stage is passed in a cocoon (fig. 1, g) of rounded oval 
form, looking not unlike a very small puffball. It is chocolate colored, 
of firm, nearly parchment-like consistency, and roughened opaque on 
the outer surface. It measures about four-tenths of an inch in its 
longer diameter and three-eighths inch in the shorter. 


Among the notes of the Bureau of Entomology is one copied from 
Riley's notebook recording the occurrence of the larvae on chestnut 
at South Pass, 111., in August, 1869. It contains a good description 
of the larva, and states that it feeds on the edges of the leaves, de- 
vouring every particle as smoothly as if cut with a pair of scissors. 
Pupation takes place about September 20. It is worthy of note that 
Riley was of the opinion that the end of the lid of the cocoon was 


Fig. 1. — The rose slug-caterpillar (Euclea indetermina) : a, Female moth; 6, male an- 
tenna ; c, larva, dorsal view ; d, larva, lateral view ; e, spine of larva, much enlarged ; 
f, pupa; g, cocoon. All enlarged; e, greatly enlarged. (Original.) 

cut by the larva before transformation to pupa, while it is quite 
obvious that the cephalic armament of the pupa is designed for that 
purpose, the pupa constantly wriggling around and around, thus 
making the perfectly circular flap. 

October 7, 1883, larvae were found feeding on oak in Virginia, and 
at another time feeding on paw paw when in bloom at Point of 
Racks, Md. 

August 3, 1889, this species was received from Yineland, N. J., 
where it was taken on Kansas plum. 


September 3, 1896 5 the insect was reported feeding on the leaves 
of Japan plum at Barnesville, Schuylkill County, Pa. 

In 1897 Dr. H. G. Dyar published a very full account of the life 
stages of this species and gave reference to its literature. 1 The larva 
appears to have been known as long ago as 1797, when Smith and 
Abbot figured it in connection with another species of moth to which 
it did not belong, namely, " Limacodes cippus." Under this name 
the species is mentioned by Harris. 2 The moth was not described 
until 1832. 3 

The recognized synonyms of Euclea indetermina are as follows: 
Callochroa viridis Reak., G. vernata Pack., and Parasa chlons Grote 
et auct. (non H.-S.). 

As remarked by Dr. Dyar, the larvae feed on various kinds of 
low-growing bushes. The list of food plants observed includes rose 
(Rosa spp.), wild cherry (Primus spp.), oak (Quercus spp.), chest- 
nut (Castanea dentata), hickory (Gary a spp.), paw paw (Asimina 
triloba), bayberry or wax myrtle (Myrica cerifera) , flowering dog- 
wood ( Gornus florida) , plum, apple, and pear. 


The various descriptions which have been furnished of this species 
agree in many easily observable particulars, but differ somewhat in 
detail. All writers seem to agree in stating that the larvae mature 
during September, but it will be noted that the specimens which were 
received from West Virginia had matured August 20. 

Eggs are deposited during July, in small groups slightly imbri- 
cating or overlapping, and hatch in about nine days. The larvae 
generally mature toward the middle of September, remaining on the 
underside of the leaves — something unusual considering their con- 
spicuous coloration. The larvae or caterpillars undergo eight dis- 
tinct stages, and occasionally nine, before transforming to pupae, 
and it has been observed that in stage I, which is passed rapidly, 
they take no nourishment. The species hibernates in its cocoon, and 
the moth has generally been observed to issue in July. 

As to the manner of forming the cocoon in confinement, all of the 
cocoons reared by the writer were attached to some object. Mr. M. V. 
Andrews, 4 who reared hundreds of this species in confinement, states 
that in all crises it either forms its cocoon adherent to the stem of the 
food plant or, occasionally, draws two leaves together for a shelter. 
There appears to be a somewhat general agreement, however, that 
in nature the cocoons are formed on the ground among loose rubbish. 

1 Journal N. Y. Ent. Soc, vol. 5, pp. 10-14, pi. 2, 1897. 

2 Harris. T. W., Insects Injurious to Vegetation, Flint ed\, 1862, p. 421. 

3 Boisduval, Cuvier's Animal Kingdom, pi. 103, fig. 8, 1832. 

4 Psyche, vol. 2, p. 271, 1879. 


This species is of equal interest with the saddle-back caterpillar, 
with which it has been compared in previous pages, not alone on ac- 
count of its beauty in all stages and its habits, but because of the 
urticating or stinging spines borne by the caterpillars. At the bases 
of these spines are glands which secrete an irritating fluid similar in 
its effect to that of nettles. It follows that rough handling of the 
caterpillars results in the breaking off of the tips of these spines, 
which enter the skin and release a small drop of the irritating liquid, 
producing a burning sensation which varies in intensity according to 
the person exposed. 


In case only a few rosebushes or young trees are attacked, hand- 
picking is ample for controlling this insect, the precaution being 
taken to use a glove, thus avoiding being " stung." Should the cater- 
pillars occur on several plants, and if a spraying outfit is available 
which may be used without danger of poisoning to human beings, a 
spray of Paris green or arsenate of lead may be applied. 

ADDITIONAL COPIES of this publication 
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Office, Washington, D. C, at 5 cents per copy